Work holding, positioning, and feeding mechanism

ABSTRACT

A semi-automatic programmed cam controlled fluid actuated mechanism which holds, sequencially positions and pressure feeds various portions of rough workpieces such as, foundry castings, and forgings into a multi-pointed cutting tool of a machine tool for snagging gates, risers, sprues and other unwanted material therefrom. The mechanism is adapted to be fixed adjacent the cutting tool of a machine and can move the workpiece in a number of different directions about a plurality of axes to perform the necessary operations in any desired preselected programmed sequence. Workholders designed for each specific casting can be interchangeably mounted on the work support. Control means comprising programmable stepping switches, with numerous contacts and easily adjustable cams actuating fixed limit switches are provided to actuate various fluid directional valves, fluid motors, and movable components in the proper sequence and directions to produce the desired motions.

United States Patent 1 91 Pettee et a1.

WORK HOLDING, POSITIONING, AND

FEEDING MECHANISM Primary ExaminerHaro1d D. Whitehead Attorney, Agent,or Firm--Walter Fred [75] Inventors: George H. Pettee, Sterling; EdwardR. Blake, Worcester, both of Mass. I 1 57 ABSTRACT [73] Assignee: NortonCompany, Worcester, Mass. I

v A sem1-automat1c programmed cam controlled fluid [22] F1led1 Nov. 1,1971 actuated mechanism which holds, sequencially posi- [21] APPL NO:194,578 tions and pressure feeds various portions of rough workpiecessuch as, foundry castings, and forgings Related Apphcatlmv Data into amulti-pointed cutting tool of a machine tool for [63] Continuation ofSer. No. 59,433, July 30, 1970, snagging gates, risers, sprues and otherunwanted maabandonedterial therefrom. The mechanism is adapted to befixed adjacent the cutting tool of a machine and can U-S- CI. T, movethe workpiece in a number of different direc- 269/71 tions about aplurality of axes to perform the neces- [51] Int. Cl B241) 7/00 saryoperations in any desired preselected pro- F 0f sealfch n 3 ,2 grammedsequence. Workholders designed for each 269/71 specific casting can beinterchangeably mounted on the work support. Control means comprisingprogram- [56] References Cited mable stepping switches, with numerouscontacts and UNITED STATES PATENTS easily adjustable cams actuatingfixed limit switches 3,151,424 10/1964 Ranel1i.. 51/232 are P1ovidedactuate various fluid directimlal 835320 11/1906 pomemyw H 51/237valves, f1uid motors, and movable components in the 3,058,267 10/1962Read 51/216 X proper sequence and directions to produce the desired3,492,895 2/1970 Greylock 51/216 X motions. 1,509,904 9/1924Salisbury.... 51/95 693,912 2/1902 Sellmayer 51/232 v 22 Clams, 9 DrawmgFigures I Q5 '3 1 4A 76 IN 2 142 L57 58 mimmum mm 3.797373 sum 1 0F 5INVENTORS GEORGE PETTEE.

E0 vv o R. BLA KE PATENTEDMAR 1 9 1974 3.7871173 SHEET u F 5 V7303 LS4 I726 L INVENTORS GsozssuPe-rrss EDBWARDIZBLAKE AGENT VC /2 H V 5.8

WORK HOLDING, POSITIONING, AND FEEDING MECHANISM CROSS REFERENCE TORELATED APPLICATIONS v This is a continuation of application Ser. No.59,433 filed July 30, 1970, now abandoned.

BACKGROUND OF THE INVENTION 1. Field of Invention The invention relatesto snagging off unwanted material from rough castings. Particularly itconcerns a mechanism adapted to hold and which automatically positionsand feeds various portions of a casting in a programmed sequence into adriven multi-point cutting tool, such as, the abrasive wheel or belt ofa snagging grinder.

2. Description of the Prior Art In the past, it has been the custom toremove gates, risers, sprues and other unwanted material from castingsby having a worker manually hold, position, and feed those portions ofthe casting to be removed into the cutting too]. Also, there existsdevices with pressure bars and fluid cylinders for assisting the workeror operator to feed the castings into the cutting tool such as theabrasive snagging wheel or belt of a typical floor stand grinder.However, these devices still required manual positioning of thedifferent portions of the casting thereon in relation to the cuttingtool. There is also shown in U. S. Pat. Nos. 693,912, 835,320, 1,509,904and 3,151,434 various work holders for polishing and buffing machines.Generally those work holders are movable in but two directions toposition the workpiece and continuously rotate and/or reciprocate andhold substantially accurately machined regular circular shapedworkpieces relative to the wheel. In contrast the applicants mechanismcan hold, position and feed various portions of regular and irregularshaped unmachined workpieces, castings, and forgings with roughinaccurate locating or reference surfaces thereon.

Further, the prior art disclosesmany types of nonanalagous numericallycontrolled precision machine tools with components movable aboutnumerous axes. The precision built into these machines are not requiredfor rough snagging operations on castings and the extremely high costcan not be'tolerated by the foundry industry. Recently however thefoundries have been unable to attract a sufficient number of workers todo the strenuous manual work. Therefore, this useful inexpensiveinvention fulfills a need within the economics of the industry, andwhich is helpful to both the workers and the industry.

SUMMARY OF THE INVENTION A base or support frame is adapted to be fixedto and supported on or adjacent a machine with a driven multi-pointcutting tool. A carriage is pivotably and slidably mounted on the baseframe and comprises an elongated support shaft slidably mounted in thesupport frame about a horizontal longitudinal axis substantiallyparallel to the axis of rotation of means supporting the cutting tool inthe machine. A'pair of spaced upwardly extending lever arms each have alower portionpivotally mounted to an opposite endportion of the supportshaft, and spaced upper end portions opposite the multi-point cuttingtool. A fluid operated cylinder fixed to the support frame traverses theshaft and the lever arms parallel to the axis of rotation of the cuttingtool support means. Adjustable cams movable with the lever arms actuatefixed limit switches to control the extent of movement in oppositedirections and to initiate subsequent movements.

A work support head is pivotally mounted between the upper end portionsof the lever arms for rotary movement about a pivot axis substantiallyparallel to the support shaft and the axis of rotation of the cuttingtool. Movable with and relative to the work support head is a workholder rotatably mounted on the work support head for rotation about anaxis normal to the pivot axis. A fluid cylinder for actuating the workholder is fixedly attached to the work support head. A rotatable driveshaft extends axially along the pivot axis from one side of the worksupport head and has gear teeth thereonengaging a lock pin lever armmounted thereon. About the drive shaft, adjacent the lock pin arm, is atorque arm with a short lever arm extending to the end of lock pin arm.A fluid actuated tapered aligning lock pin extends through alignedtapered holes in both of the arms. 'A fluid operated lock pin actuatingand deactuating cylinder and a rotary actuator to rotate the drive shaftis fixed to the torque arm having a long lever arm extending oppositethe short lever arm. The long lever arm is attached to a ball joint atan upper end of a tie bar or rod having a ball joint at its oppositelower end attached to the base or support frame whereby a first four barparallel linkage system is provided to maintain a-definite relationshipbetween the workpiece and the cutting tool when the lever arm togetherwith the work support head are pivoted in a fixed are about the axis ofthe support shaft.

The rotary actuator comprises a fluid actuated rack piston engaging agear fixed to the drive shaft and pivots the lock pin arm, the worksupport head, and other components attached thereto when the lock pin iswithdrawn. A cam support disc is keyed to the drive shaft and hasadjustable cams thereon to engage fixed limit switches controlling theextent of pivotal movement and initiating the next operation.

Fixed in axial alignment with the drive shaft and on the opposite sideof the work support head is a hollow driven shaft fixed to one rotatabledrive member of a fluid actuated clutch. The one drive member is fixedto a support sleeve to which is fixed a fluid actuated rotary motorbody. Axially aligned drive shafts extend from both ends of the rotarymotor. One of the shafts is fixed to a second rotatable drive member ofthe fluid operated clutch keyed to an internal rotary drive shaftextending back through the hollow drive shaft to a bevel gear within thework support head. An axially movable clutch member is shifted by fluidpressure to couple the first and second drive members and thereby causesthe work head, the clutch, and the rotary fluid motor to pivot togetherwhen the rotary actuator is energized. Upon releasing the fluid pressurein the clutch and actuating the lock pin cylinder, the work support headis fixed against pivotal movement and the-rotary motor can be actuatedto rotate the internal drive shaft relative to the hollow shaft. Thebevel gear rotates and engages another bevel gear fixed to a shaftattached to the work holder, whereby the work holder is rotated about anaxis normal to the pivot axis of the work support head.

On the carriage is a link bar pivotally mounted at one end between theupper and lower ends of each of the lever arms. The link bars extendforwardly away from the machine tool substantially parallel to oneanother and are pivotally connected to opposite ends of a pivotablecross feed bar or link having an elongated slot between the oppositeends thereof. The end of a fluid pressure work feed cylinder ispivotally attached to the fixed base, support frame, or a pivot supporton or adjacent the machine tool and extends longitudinally with the axisof the piston rod therein normal to and pivotal about a horizontal axissubstantially parallel to the axis of the traversable support shaft. Anadjustably feed screw is fixed to the end of the piston rod and extendsinto engagement with a rotatable nut or hand wheel fixed against axialmovement within the elongated slot in the cross feed bar.

A second tie rod with ball joints at opposite ends connects the baseframe with a cross member fixed to the forward ends of the link barswhereby a four bar linkage system is provided to approximately maintainthe force relationship between the fluid pressure cross feed cylinderforce and the cutting tool when the carriage is rocked towards and awayfrom the cutting tool. A cam support including a plurality of adjustablecams moves with the carriage and engages limit switches to control theextent of movement toward and away from the cutting tool and also startsa subsequent movement.

The work holder for each casting has a support base against which thecasting is clamped and designed to be interchangeable and mate with auniversal mounting plate fixed to a rotatable shaft.

A plurality of conventional programmable stepping switches have aplurality of contacts adapted to close and open at the proper timeconnected in series with the various limit switches. The limit switchesupon being actuated energize the stepping motors in unison whereuponsome contacts are programmed to close and energize solenoid operatedfluid directional flow control valves in the proper sequence. Others areprogrammed to open and de-energize or prevent energization of solenoidoperated fluid directional valves in the proper sequence. Theenergization and de-energization of the solenoid operated directionalvalves directs fluid under pressure to the various components which holdposition and feed various portions of the casting into the cutting toolin the proper sequence.

It is therefore the primary object of this invention to provide aneconomical work holding, positioning, and feeding mechanism, withsimple, easily adjustable, readjustable, and programmable control meansfor automatically, sequencially positioning and pressure feedingdifferent unwanted portions of rough workpieces properly into, and forremoval by, a driven multi-point cutting tool of a machine tool situatedadjacent the mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1, is a perspective view of thework holding, positioning and feeding mechanism of this inventionassociated with a floor stand snagging grinder, shown by way of exampleonly as one of the many types of machines with a driven multi-pointcutting tool with which the invention may be utilized;

FIG. 2, is a side view in elevation, partly in section of the workholding, positioning, and feeding mechanism of the invention shown byway of example only attached to the base of the snagging grinder shownin FIG. 1;

FIG. 3, is a plan view, shown partly in section of the invention shownin FIG. 2;

FIG. 4, is a front view in elevation with portions shown in section ofthe invention shown in FIG. 3;

FIG. 5, is sectional view taken, approximately on line 5 5 of FIG. 2,through a portion of the work support head and a work holder supportedthereon for holding a specific casting shown by way of example only;

FIG. 6, is an enlarged sectional view of the upper end of the workholder showing the collapsed and expanded positions of the pivotableclamping members and the camming surfaces therein;

FIG. 7, is sectional view taken on line 7 7 of FIG.

FIG. 8, is a diagrammatic view showing the various movable components ofthe invention, the fluid pressure operated means for moving the variousmovable components, and the directional control means therefor; and

FIG. 9, is an electrical diagdam of the electrical control means of theinvention including a plurality of conventional programmable stappingswitches.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S) The invention will bedescribed by way of the example only in association with a conventionalfloor stand type grinder G for snagging material off foundry castings asshown in the drawings. The grinder G has a mu]- ti-point'cutting tool orgrinding wheel T rotatably supported and driven in the well known mannerabout its axis of rotation by a conventional drive motor GM on a base Bof the grinder. However, other types of machines maybe used incombination with the invention and which have multi-point cutting toolssuch as abrasive belts, milling cutters, fly cutters and and the likemoving around the axis of rotation of means supporting the multi-pointcutting tool to remove the unwanted material from the rough castings. Anexample of a typical casting of which is indicated by the letter C.

Referring to the drawings there is shown a work or workpiece holding,positioning, and feeding mechanism 10 with which this invention isconcerned situated adjacent the cutting tool and front side of thegrinder G. The mechanism 10 comprises a base frame or support frame 12which is fixed relative to and in this instance to the base B of thegrinder G. However, the support frame could be substituted by a pedestalor base fixed to the floor and relative to the machine base B. Thesupport frame 12 comprises a base plate 12a fixed, as by bolting, to thebase B of the grinder G extending outwardly and away from the front ofthe machine. Fixed at one end to the base plate are a pair of spacedsupport members or I beams 12b and 12c. Each of the I beams have abearing block 12d fixed thereto intermediate the opposite ends thereofwith axially aligned cylinderical bearing holes l2e therein. The axis ofthe bearing holes l2e is substantially horizontal and parallel to theaxis of rotation of the grinding wheel or cutting tool T. A reinforcingtie bar 12g extends-between and is fixed to the I beams and to anoutboard support member or bar 12h fixed at one end to the base plate12a and extends outwardly therefrom to the right side of I beam 120, asviewed in FIG. 3 and FIG. 4, to

an unsupported end fixed to a traversing cylinder support plate ormember 12j.

An elongated support shaft 14 extends through the aligned bearing holes12e and with its opposite ends extending beyond the I beams 12b and 120.The shaft 14 being pivotable about and slidable axially along itslongitudinal axis relative to the base or support frame 12, the cuttingtool, and the snagging machine or grinder G.

Attached to, slidable with, and either pivotal with or relative to theshaft is a carriage 16 which may include the support shaft 14 comprisinga pair of upwardly extending spaced lever or rock arms 16a and 16bconstructed in this instance from structural U-shaped channel iron. 7

The lower end portions of the lever arms have axially alignedcylinderical bearings 16c therein through bearing holes of which theshaft 14 extends. There are conventional retaining or snap rings 16dadjacent opposite ends of the bearings 16c which snap into spacedgrooves in the shaft to prevent relative axial motion therebetween.Ifdesired means, such as, conventional pins or set screws could be usedinstead of or'in addition to the snap ringsto prevent relative axialmotion between the shaft and the lever arms. Alternatively, the supportshaft 14 could be fixed to the I beams 12b and 120 and relative to thebase frame 12. The carriage 16 could then pivot and slide axiallyrelative to the shaft.

As shown the lever arm 16a is supported on a portion of the shaft 14between the I beams 12b and 12c and the lever arm 16b on a portion ofthe shaft between I beam 120 and the cylinder support plate l2j. In FIG.2 it can be seen that the upper end portions of the rock or lever armsare aligned axially'and situated at an angle of approximately 45relative to their lower portions. A tie plate or connecting web 16dextends between the upper portion and fixes the relationship between thelever arms so they move together in unison.

As viewed in FIG. 2 and 3 the upper and lower portions of lever arm 16aare located in one plane whereas the upper and lower portions of leverarm 16b are offset and in different planesThe upper portions beingaxially spaced closer together than their lower portions. I In the upperangled portions of the lever arms 16a and 16b are axially alignedcylinderical support bearings l6e and. 16f with axially aligned bearingholes in which is pivotally mounted and supported work support means ora work support head 20 for movement about a pivotaxis substantiallyparallel to and movable relative to the longitudinal axisof the supportshaft 14 and the axis of rotation of the cuttingtool T.

The work support means or head 20 comprises a work holdersupport or gearhousing 22 which in this instance is a substantially hollow, flat sided,cube shapedv structure. A rotatable or pivotal drive shaft 24 is fixedto and extends from the left side of the housing 22 and passes throughthe support bearing 16e in lever arm 16a. The drive shaft 24 has asplineor gear tooth 24:) on the large diameter portion thereof extendingbeyond the bearing l6e, a threaded portion, and adjoining reducedportions 24b and 240 of lesser diameter.

A lock pin lever arm or angular work positioning arm 26 has a taperelocating hole 26a spaced from a central hole 26b with internally formedmating spline or gear tooth meshing or engaged with the gear tooth 24aon the large diameter portion of the shaft 24. A threaded retainer nut28 on the threaded portion maintains the lever arm 26 in position.

Means are provided for pivoting the work support head or means 20relative to the carriage 16 and the cutting tool T about the pivot axisof the shaft 24 and the bearings 16c and 16f in the lever arms 16a and16b comprising a conventional fluid operated rotaryactua tor 30 such as,Model 3720 ll 10 commercially available from Flo-Tork Division of AllenElectric And Equipment Company, Orrville, Ohio.

The rotary actuator 30 comprises a housing or body 30a with spacedaligned bearings 30b through axially aligned bearing holes of which thereduced portion 24b of the shaft 24 extends and supports the actuator30. A gear 32 is fixed to the rotatable drive shaft portion 24b andmeshes with the rack teeth of a transversely movable rack piston 34slidably mounted in a cylinder bore in the body 30a of the actuator 30.

Fixed, as by bolting, to a side of the rotary actuator body 30a andadjacent the positioning arm 26 is a torque arm 36 having a short leverarm with a tapered hole 36a shown in ,axial alignment with the locatingho'le 26a. The torque arm 36 has a clearance hole through which theshaft portion 24b extends and from the axis of which a long lever armextends opposite the short lever arm and away from the front of themachine. It is connected at its end portion to the upper ball joint atthe upper end of a tie rod or bar 38. The tie rod 38 extends downwardlyand has a lower ball joint at its opposite lower end connected to theforward unsupported end of the I beam 12b.

In FIG. 2 it can be seen that the relative positions of the axes of theball joints and of the shafts l4 and 24 are always maintained atpredetermined fixed distances apart by what is known conventionally as afour axes or four bar parallel linkage system. The four bar linkagesystem serves to maintain the initial predetermined angular position ofthe work support head 20 and the casting C thereon as shown in phantomlines in FIG. 2 as the carriage 16 is pivoted about the relativelystationary longitudinal axis of the support shaft 14 to feed the castingC into the cutting tool T.

The torque arm 36, the tie rod 38, and the I beam 12b serve to supportand to resist the forces exerted in both directions by the fluidoperated rotary actuator 30. In addition the ball joints at oppositeends of the tie bar 38 allow the cariage 16, together with the worksupport head 20 to be traversed predetermined limited amounts inopposite directions along the lingitudinal axis of the elongated supportbar As the carriage 16 is movedsubstantially parallel to the axis ofrotation of the grinding wheel T the center distance between the balljoints of the tie rod 38 vary only slightly without substantiallychanging the initial relationship between the four bar parallel linkagesystem.

Means are provided for aligning and locking the torque arm 36 and thelock pin lever or angular positioning arm 26 together to-preventrotation of the work support head 20 by the rotary actuator 30ormachining forces. The aligning and locking means comprises. a fluidactuated and'deactuated lock pin cylinder 40, fixed, as by bolting tothe backside of the body 3011 on the. rotary actuator 30. A piston 42 isslidably mounted within a cylinder bore in the cylinder 40 from which apiston rod 44 extends substantially parallel to the axis of the shaft 24and in axial alignment with the aligned tapered locating holes 36:; and26a. Fixed to the end'of the piston rod 44 is a conical locating pin ortapered lock pin 46 in mating engagement with and aligning the taperedholes 36a and 26a in the torque arm 36 and the lock pin lever arm 26.

Upon actuating the four way directional valve VD fluid under pressure isadmitted into the left side of the cylinder bore and the piston forcesthe tapered lock pin 46 to the right to align and lock the lock pinlever or angular positioning arm 26 to the torque arm 36 and preventrelative movement therebetween. However, upon deactuating the valve VDand shifting the piston 42 to the left, only moves the tapered lock pin46 out of the tapered hole 26a and clear of the lock pin lever arm 26. Aportion of the tapered pin 46 remains within the tapered hole 36a intorque arm 36 which is fixed relative to the cylinder 40.

With the tapered locking pin 46 withdrawn, fluid under pressure can beadmitted, by actuating a four way directional control valve VB, toeither end of the bore in the rotary actuator 30 to move the piston 34therein. Movement of the piston 34 causes the rack tooth thereon torotate gear 32, the shaft 24, and hence pivot the work support headrelative to the carriage 16 towards and away from the cutting tool orgrinding wheel T.

Adjustable control means 50 are provided for limiting the amount ofpivotal and angular movements of the work support head 20 and thecasting C about the pivot axis of the drive shaft 24 towards and awayfrom the cutting tool T and for initiating further work feeding and/orpositioning movements of the mechanism 10. The adjustable control means50 comprises a cam support disc 52 fixed to as by a set screw androtatable with the portion 240 of the shaft 24. On the periphery of thedisc 52 is fixed at predetermined spaced angular positions a pluralityof adjustable cams 54, 54a and 54b. An enclosure or cabinet 56 with anaccess door is fixed to the left side of body 30a of the rotary actuator30 and through a wall of which extends the shaft portion 24c situatedwithin a chamber therein. A plurality of conventional limit switchesLS5, LS6, and LS are fixed to the wall of the cabinet in a predeterminedangular position about the pivot axial of the shaft portion 240. Each ofthe limit switches being actuated by at least one or more of the cams 54to sequentially stop a previous work feed or positioning movement and/orinitiate another work feeding or positioning movement.

The work support head 20 has integrally formed therewith or fixed to theopposite or right hand side of the housing 22 a hollow rotatably drivenshaft 60 extending through the support bearing 16f in axial alignmentwith the pivot axis of the pivotal drive shaft 24. The opposite end ofthe driven shaft 60 is fastened to a flange 60a fixed relative to arotatable driven cylinder 62a of a conventional fluid operated clutch 62such as Model LWB commercially available from Horton ManufacturingCompany, Inc., Minneapolis, Minn. Slidably mounted within the drivencylinder 62a is an axially movable clutch drive piston or friction disc62b keyed or splined, in the well known manner not shown, againstrotation relative to the cylinder 62a. The clutch drive piston 62b isadapted to be forced by fluid under pressure into driving engagementwith the other driven clutch member or disc 62c of the clutch 62. Uponactuating a two way directional control valve VE fluid under pressure isadmitted into the cylinder 62a to force the drive piston 62b intoengagement with and drive the disc 62c. Deactuating valve VE allowsfluid to exhaust and disengage the drive piston 62b from the disc 62c. Acylinderical hub 62d integral with the disc 62c extends through thecentral bore of the drive piston 62b and has a anti-friction bearing 62cmounted on a portion thereof extending over and keyed to a rotatabledriving gear drive shaft or internal drive shaft 66 extending through asleeve 68 within the hollow driven shaft 60. The outer race of thebearing 62e rotates together with the hollow shaft 60, the cylinder 62a,and the piston 62b relative to the inner race rotatable with the hub62d, the disc 62c, and the drive shaft 66. The internal drive shaft 66has a end portion extending through and journalled in an antifricationbearing 70 fixed against axial movement in the right hand side wall ofthe work support housing 22. A driving gear or bevel gear 72 is fixed bysuitable means, such as by pining or bolting it to the shaft 66, and isrotatably supported within the inner race of the bearing 70 in thehousing 22. The bevel gear 72 meshes and drives a second bevel gear orwork holder drive gear 74 fixed and keyed to a tubular rotatable workholder drive shaft 78 journalled in a pair of spaced antifrictionbearings 80 and 82 in the housing 22. Drive shaft 78 extendslongitudinally through the upper and lower walls of the housing 22 andis rotatable about a normal axis perpendicular to the pivot axis aboutwhich the pivotal'drive shaft 24, the internal drive shaft 66, and thehollow driven shaft 60 rotate.

The bevel gears 72 and 74 are selected to have preferably a 1:1 ratio sothat the shafts 66 and 78 rotate equal angular amounts about theirindividual axis.

Fixed and keyed to the upper end of the workholder drive shaft 78 is aworkholder support base or adaptor 84 on which can be interchangeablymounted various workholders specifically designed to fit the base 84 andto hold the particular workpiece or casting C to be worked upon by themachine G.

In this instance the workholder has a work support arbor 92 with acentral hole and a work support or work drive flange 92a adapted to bebolted to and mate with the adaptor or workholder support base 84.Extending upwardly from and normal to the work support flange 92a is anelongated tubular work locating or aligning shaft or portion 92b ofsufficient length to pass through spaced roughly aligned cast bores atopposite ends of the casting C. The casting C in this particularinstance is a differential housing with a ring gear support flange froma peripheral portion of which must be removed excess cast material knownas a gate. The housing has side walls extending axially from the supportflange with large opposed access openings therein around which excessundesirable cast material, such a flash, is to be removed from each ofthe opposite roughly cast substantially flat parallel surfaces aroundthe openings as shown in the drawings. The ring gear support flange ofthe casting C rests against the work support flange 92a and has alocating hole therein into which projects a combination work drive andwork orienting or locating pin 94 fixed in the flange 92a. In theopposite upper pointed end portion of the tubular work locating shaft92b is a transversely extending work clamp guide slot 920 at the bottomof which are work clamp retracting cam surfaces 92d on opposite sidewall portions around the central hole through which the locating shaft92b extends.

A pair of substantially identical work clamps or fingers 96 arepivotally mounted to the upper end portion of a work clamp actuating rod98 slidable axially within the central bores of the tubular locatingshaft 92b and the tubular workholder drive shaft 78.

The upper end portion of the actuating rod 98 also has a slot 98aaligned with and of substantially the same width as the transverse slot920. Within the slot 98a are situated beside one another, end portionsof the work clamps 96 with aligned pivot holes through which extends apivot pin 100 connected to the actuating rod 98. The work clamps orfingers 96 extend outwardly in opposite directions from the pivot pin100 and each have end portions within the slots 920 with upper and lowercam following or engaging surfaces thereon. Within the slot 920,adjacent the upper cam engaging surfaces of the work clamps 96, is aclamping cam 102 fixed as by conventionally bolting or pinning it to theopposite wall portions of the tubular work locating shaft 92b as shown.On the clamping cam 102 is a pair of spaced convex camming surfaces 102aeach of which engages an upper convex cam engaging surface 96a on eachof the work clamps or fingers 96. The lower cam engaging surfaces 96b onthe work clamps 96 are substantially identical straight surfaces whichin one position clamps against the endsurface of the casting C and inanother position engages the work clamp retracting cam surfaces 92d torelease the workpiece or casting C. i

Means including a fluid pressure operated work clamping cyinder 104'is'provided for shifting the actuatin'g rod 98 axially in oppositedirections and thereby cam thework clamps 96 into and out of clampingengagement with the casting C. The cylinder 104 is fixedly attached toand spaced from a mounting plate 105 and the bottom wall of the housing22 of the work support head 20, by conventional bolts and spacers shown.A piston 108 is slidably mounted within a cylinder bore in the cylinder104 and rotatably mounted on an anti-friction bearing 1 having an innerrace or hub fixedly attached to the lower opposite end of the actuatingshaft or rod 98. A resilient member such as a coil spring 1 12 isinterposed between the end of workholder drive shaft 78 and a dust sealwasher or cap 114 seated against the inner hub or race of bearing 110.The spring 1 12 tends to bias the piston axially away from the housing22 and shifts the actuating rod 98 downwardly causing the work clamps 96to engage the cam surfaces 92d and thereby retracted within the slot 92cand periphery of the work locating shaft portion 92b. After which, acasting C can either be removed or placed thereon.

Whena two way directional fluid control valve VC is actuated, fluidunder'pressure passes into the cylinder 104 and shifts the piston 108,the actuating rod 98,

and the work clamps which are forced into clamping engagement with thecasting C by the convex cam surfaces 1020. Thus the previously loadedcasting C orientedby the pin 94 is forceably clamped against the workdrive or support flange 92a. Upon deactuating the control valve VC theworkpiece is released and the spring l12'returns the piston to itsinitial position while fluid exhausts from the cylinder 104 through thecontrol valve VC.

A rotary fluid operated motor 120 is provided for rotating the clutchdisc 62c, hub 62d shaft 66 bevel gears 72 and 74, shaft 78, and theworkholddr 90 relative to the housing 22 about an axis normal to thesubstantially horizontal movable pivot axis of shaft 24, about which thework support head 20 pivots. On the rotary fluid operated motor 120 is ahousing with a mounting flange 120a a one end thereof bolted to an endsurface of a cylindrical motor support sleeve 122. The motor supportsleeve extends axially and is fixed at its oppostie end to the flange60a of the hollow shaft 60 and the driven cylinder 62a of the clutch 62.A pair of axially aligned rotatable output shafts or drive shafts l20band 1200 extend outwardly from opposite ends of the motor 120. Therotary motor 120 may be any suitable commercially available conventionaldouble shafted reversible fluid operated motor, such as Model PRV-22commercially available from Hartman Hydraulics Division of KoehringCompany, Racine, Wis.

To the drive shaft 12% is fixed and keyed one flange or member of adrive coupling 124 having a second member or flange fixed and keyed to ashaft 62g fixed to the hub 62d of the clutch 62.

On the opposite end wall or surface of the housing of motor 120 is fixedanother enclosure or cabinet 126, with an access door, similar to thecabinet 56. The shaft 120C of the rotary fluid motor 120 extends throughthe wall of the cabinet'l26 and into a chamber therein.

Adjustable control means are provided for controlling the extent of theangular rotary movements of the workholder and the casting or workpieceC about the axis of the shaft 78 and to initiate further work feedingand/or work positioning movements of the mechanism 10. It comprises acam support disc 128 fixed to and rotatable with the shaft 120C and hasa plurality of adjustable cams-130 and 130a fixed at predeterminedangular positions about its periphery and the axis of the shafts l20cand 66. Fixed to the wall of the cabinet 126 are a plurality ofconventional limit switches LS3, LS4 and L811. Each limit switch isactuated by at least one or more of the cams 130 to sequentially stop aprevious work feeding or work positioning movement and/or initiateanother work feeding or positioning movement.

It can be seen that when the clutch 62 is actuated the clutch disc 620is coupled and locked to the clutch cylinder 62a and against relativemovement by the clutch drive piston 62b. Upon withdrawing the taperedlock pin 46 and actuating the rotary actuator 30 shaft 24, lock pinlever arm 26, work support head 20, workholder 90, hollow shafts 60,shaft 66, clutch 62, support sleeve 122, coupling 124, fluid motor 120,cam support disc 128, and the cabiet 126 all rotate together. When thetapered lock pin 46 is inserted into the locating hole 26a of the leverarm 26, the work support head 20 cannot be pivoted. Howevenwhen theclutch 62 is deactuated with clutch disc 62c is now disengaged from andfree to be moved by the rotary fluid motor 120 relative to the clutchdrive piston 62b, the clutch cylinder 62a and the hollow shaft 60.Actuatingand shifting a four way control valve VA in one direction willdirect fluid under pressure to rotate the shafts 120b and 120a of themotor 120 in one direction. Actuating and shifting the control valveVAin the opposite direction will rotate the drive shafts 120b and 1200 inthe opposite or re verse direction. Hence, rotation of the drive shaftsl20b and l20c in either direction causes a corresponding rotationalmovement of the cam support disc 128, coupling 124, shaft 62g disc 62c,shaft 66 the bevel gears 72 and 74, shaft 78, and the workholder in thedrive train coupled thereto. That is, when the shafts, k and 1200, camsupport disc 128, and the bevel gear 72 rotate clockwise, as viewed fromthe right-hand end of the drive shaft 1200 in FIGS. 3, 4, and 8; thebevel gear 74, shaft 74, and the workholder 90 are likewise rotatedclockwise as viewed from the upper pointed end of the work locatingshaft 92b of the work support arbor 92 in FIGS. 3, 4 and 8.

Cross feed means 140 are provided for simultaneously moving the carriage16, work support head 20, and the workholder 90 about the longitudinalaxis of the support shaft 14 towards and away from the cutting tool Tfor either positioning, feeding and/or retracting the casting C relativeto the cutting tool T. The cross feed means or the carriage may comprisea pair of spaced link bars 142 each of which is pivotally connected atone of its rear end portions to a pivot pin or screw 144 fixed to thelower portion of the lever arms 16a and 16b between the axes of theshafts 14 and 24. From the lever arms 16a and 16b the link bars 142extend outwardly away from the cutting tool substantially parallel toeach other and each is fixedly connected at its forward end portion to across member orbar 142a. A bracket 142b is fixed to the cross tie bar142a substantially midway between the link bars 142 and to which isconnected an upper ball joint of another tie rod or bar 148 similar tobut of shorter length than the tie rod 38. The second tie rod 148extends downwardly and has a lower ball joint connected to the forwardend of a channel iron or bracket 150 fixed at its opposite rear end tothe I beam 120 and from which it extends outwardly and downwardly at aslight angle therefrom.

It can be seen that another four pivot or four bar linkage system isprovided comprising the relatively fixed pivot axis of the shaft 14 andthe lower ball joint stud of the shorter tie rod 148 and the relativelymovable pivot axes of the pivot pins 144 and the upper ball joint i studof the tie rod 148. Thus the force applied by the cross feed cylinder160 through link bars 142 to the carriage 16, work support head 20,workholder 90, and support shaft 14 to the casting C for the purpose ofmachining can be held relatively constant for various positions of crossfeed toward and away from the cutting tool. Yet, the ball joints atopposite ends of the tie rod 148 allows the link bars 142 to movetogether with carriage 16 along the axis of shaft 14 parallel to theaxis of rotation of the cutting tool T.

Above the cross member 142a is a cross feed bar 152 which extendsbetween and is pivotally connected at its opposite endsto the forwardend portions of the link bars 142 by axially aligned pivot studs orscrews 154. The cross feed bar 152 has an elongated bearing slot 152a inwhich is rotatably mounted a handwheel 156 having a reduced cylindricalbearing engaging portion 156a extending from a shoulder through theelongated slot 152a and a threaded central hole 156b. A retaining collaror snap ring 156c in a groove around the cylindrical portion 156aengages the opposite side of the cross feed bar 152 and prevents thehandwheel from moving axially relative thereto. However, the elongatedslot 152a allows the cross feed bar 152 together with the link bars 142and the carriage to move relative to and in a direction normal to theaxis of the threaded hole l56b in the handwheel. Therefore, the linkbars 142, the cross feed bar 152, and the tie rod 148 can also beconsidered as parts of the carriage as well as the cross feed means.Means for cross feeding the carriage together with the link bars 142,the cross feed bar and the tie rod 148 comprises an adjustable feedscrew 158 extending through the threaded central hole 156b. The screw158 is coupled at its opposite end to the end of a piston rod of a fluidactuated cross feed cylinder pivotally attached to a forwardlyprojecting base portion, or support frame bracket B fixed relative tothe base B and/or the support frame 12. The base portion or bracket Bextends'outwardly opposite the peripheral cutting face of the cuttingtool T and to which is fixed a pivot support or pivot bracket 162. Acylinder pivot pin 164 pivotally connects the end of cylinder 160 to thepivot bracket 162, in the well known manner, to pivot about a fixedhorizontal axis substantially parallel to the fixed longitudinal axis ofthe support shaft 14.

The fluid actuated cylinder 160 has an elongated cylinder bore in whichis slidably mounted a piston 160k attached to the opposite end of thepiston rod 160:- therein. The cylinder 160 has a central axis alignedwith the axis of the feed screw 158 and a plane situated substantiallymidway between the opposite axially spaced side faces of the cuttingtool T and extending substantially perpendicular to the fixed horizontalaxis of the pivot support 162.

Means are provided for controlling the extent of the cross feeding orpositioning movements of the carriage 16 comprising an elongated limitswitch support plate 166 fixed to the underside of the cylinder 160. Aplurality of limit switches LS2, LS9, LS13, and LS1 are fixed to thesupport plate 166 at predetermined intervals along the axis of thecylinder 160.

A cam support plate 168 is fixed in any suitable conventional manner tothe feed screw 158 and is movable axially with the piston rod relativeto the cylinder 160 fixed against axial movement. On the cam supportplate 168 are a plurality of spaced adjustable cams 170, and b each ofwhich actuates one or more of the limit switches shown.

Upon actuating and shifting a conventional four way directional controlvalve VZ in either one of two opposite directions, fluid under pressureis admitted to one end of the cylinder 160 to shift the piston'160btoward the opposite end of the cylinder 160. Hence, the piston rod 160e,feed screw 158, cam support plate 168, cams 170 and 170b, cross feed bar152, link bars 142, carriage 16, and the work support head 20 moverelative to the cross feed cylinder 160 and the limit switches about thelongitudinal axis of support shaft 14.

' As shown in phantom lines (in F102) the shorter center distancebetween the ball joints of the shorter tie rod 148 allows the angularrelationship between the carriage l6 and the link bars 142 to change andprovide the relatively constant cutting force as previously describedabove. The angular position of the axis of the cylinder 160 and the feedscrew 158 changes very little relative to the link bars 142 since thecylinder 160 pivots about a fixed axis causing only a small amount ofpivotal movement of the cross feed bar 152 about the pivot screws 154connected to the link bars 142. By turning the handwheel 156 relative tothe feed screw 158 the stroke of the piston and hence its positionrelative to opposite ends of the cylinder 160 can be varied and adjustedto provide the necessary amount of feed or positioning movement. Whenthe piston l60b is held against axial movement by the fluid in thecylinder 160 rotating the handwheel 156 causes the carriage to moverelative to the feed screw 158 to locate the initial starting or loadingposition of the work support head 20 and to compensate for wear andreduction in the size of the cutting tool.

Longitudinal traversing means 170 are provided for simultaneouslytraversing the support shaft 14, carriage l6, link bars 142, cross feedbar 152, the work support head 20 and the workholder 90 together alongthe longitudinal axis of the shaft substantially parallel to the axis ofrotation of the cutting tool T and relative to the base frame 14,cylinder 1 60, feed screw 158, handwheel 156 base B and the cutting toolT. The longitudinal traversing means 170 comprises a fluid actuatedcylinder 172 fixed, as by bolting, to the cylinder support member 12 ofthe base frame 12. A piston 1720 is slidably mounted within a bore inthe cylinder and to which is fixed a piston rod 172b coupled to the endportion of the support shaft 14 extending through and beyond thebearing160 in the lever arm 16b. Upon actuating and shifting a four waydirectional fluid control valve VX in either one of two directions,fluid under pressure is directed to one end of the cylinder 172 to shiftthe piston 172a, a piston rod 172b and the support shaft 14 and attachedmembers together in an opposite direction relative to the cylinder 172and the base frame 12. t

Means to control the extent of the longitudinal traversing and/orpositioning movements comprises a mgitudinal traverse limit switchsupport plate 174 fixed to a side of the cylinder 172 and to which isfixed a plurality of limit switches suchas LS7 and LS8. Fixed to andmovable with the support shaft 14 and/or the lever arm 16b is a camsupport bracket 176 extending outwardly therefrom and above the cylinder172. A cam support bar or-plate 178 is fixed to the bracket 176 and hasa plurality of adjustable cams 180 and 180a thereon which actuate thelimit switches to sequentially stop a previously initiated movementand/or initiate a work feeding or work positioning movement.

Fluid supply means are provided for supplying fluid under predeterminedpressures to the various fluid actuated components of the mechanism 10comprising a reservoir or source of fluid 190, a conventional andsuitable fluid pump P driven by a motor FM and a conventional adjustablepressure relief valve 192 connected between the main supply lines sand-the main return lines R, for maintaining the fluid in the supplylines or" conduits S at the desired pressure. Other pressure reliefvalves and pressure reducing valves are provided for operating certainof the components at pressures different than the pressure of the fluidin the main linesS. i

The fluid operated system for actuating the various components of themechanism 10 can beeither totally hydraulic or pneumatic or a mixture ofconventional hydraulic. and pneumatically operated components.Preferably ahydraulic system is more desirable where precise control isnecessary. However, .where precise control is not essential and quickaction is desired-a separate line of compressed air under controlledpres sure which is available in most foundries and manufacturing plants,can be connected separately to those particular components of thesystem. For example, the supply lines S to and the directional controlvalves VC, VE and VD could be disconnected from the hydraulic system andconnected to a separate conventional source of air under, regulatedpressure. Thus the work clamp cylinder 104, the lock pin cylinder) andthe fluid clutch 62 are quickly operated pneumatically while the rest ofthe system is operated hydraulically. To simplify the description onlyone of each different type of the directional control valves has beenshown in detail. All of the conventional four way directional controlvalves VX, VZ, VB are of the same general construction as valve VA shownin more detail and are commercially available. from a number of sourcesfor use in hydraulic and pneumatic fluid pressure systems. Specificallythe control valves VX, VZ, VB and VA shown have push type solenoids atopposite ends of a spring centered fluid directing spool with threechambers and a central exhaust passage extending between the endchamber. Energizing the solenoid shifts the spool away from thatparticular solenoid and deenergizing the solenoid allows the balancedsprings between the solenoids and the spool to return and center thespool as shown.

Likewise the two way directional control valve VB is of the same generaland conventional construction as the valve VC shown in detail. They havea single push type solenoid at one end of a fluid directing spool withtwo chambers and a return spring biasing the spool towards the solenoid.Energizing the solenoid shifts the spool towards and compresses thespring which returns the spool when the solenoid is de-energized.

The four way directional control valve VD is similar to and operates inthe same manner as does the two way control valves VE and VC, exceptthat it has an additional chamber, land, and passage to make it a fourway valve instead of a two way.

Most of the fluid actuated component and controls shown in the drawingsare conventional and commercially available from many differentmanufacturers therefore it is deemed unnecessary to describe thespecific construction of each individual conventional component as theyare well known in the art.

Programmed control means are provided within a cabinet CM for actuatingand deactuating the various components of the mechanism 10 describedabove so as to position and feed various portions of the workpiece orcasting C. into the cutting tool T in a predetermined sequence ofoperations. The programmed means comprises a plurality of conventionalstepping switches STl, 8T2, ST 3 and ST 4 whichmay be of any suitablecommercially available type such as, a linear or rotary stepping switchmechanism with either cam programmable contacts, or an equivalentelectrically programmable solid state stepping switch such as ModelMT-SO commercially available from Eagle Signal Corporation, Davenport,Iowa.

The operation of the stepping switches are well known in the art andtherefore only a brief description of their operation is deemednecessary. A stepping switch mechanism comprises basically apredetermined number of contacts, programmed means shiftedsimultaneously and incrementally one step at a time by either a steppingmotor, a step coil or an electromagnet operated ratch system whichcloses one or more of the contacts at the proper time and increent thestep switch is advanced during a, complete cycle thereof.

As shown in FIG. 9, a plurality of contacts of both of the steppingswitches STI and ST3 are connected in parallel with each other andconnected in series with the contacts of the limit switches LS1 andL313, a start push button PBZ, and a start switch SW1 all connected tothe electrical lines L1 and L2.

In a similar fashion a plurality of contacts of the stepping switchesST2 and ST4 are shown connected in parallel with each other andconnected to electrical lines L1 and L2 in series with the solenoidsSA+, SA, 88+, 53-, 82+, 82-, SX+, SX, SD, SE, and SC of the respectivefluid pressure directional control valves associated therewith.

As shown, the conventional electromagnetic step coil and step mechanismSC of the stepping switches STl and ST2 are connected in parallel andstep together. Likewise the conventional electromagnetic step coil andstep mechanism SC of the stepping switches ST3 and ST4 are connected inparallel and step together. However, the stepping switches ST3 and ST4do not begin to operate until the stepping switches STl and ST2 havecompleted one cycle of a predetermined number of increments. By thistime only a predetermined number of the total number of the programmedwork positioning and feed movements necessary to finish the casting Chave been performed. All of the programmed contacts of stepping switchesSTl and ST2 have been utilized. Therefore, a set of contacts of each ofthe stepping switches STl and ST2 are closed on the last step to directall future electrical energy from the limit switches and from L1 throughthe programmed contacts of the stepping switches ST3 and ST4.

The remaining sequence of the work positioning and feed movements arenow under the control of the programmed stepping switches ST3 and ST4which operate simultaneously in same manner as the switches ST] and ST2.Only when a limit switch contact and the contact of the stepping switchin series therewith is programmed to be closed, can electrical energyfrom line L1 simultaneously energize the electromagnetic coils of eitherthe stepping switches STl and ST2 or 8T3 and ST4. Hence, the cams canmove back and forth over and actuate any of the limit switches connectedin series with the programmed open contacts of the stepping switcheswithout affecting the stepping switches.

Each of the stepping switches has its own individual predeterminedprogram which is synchronized with one another to either open, holdopen, close or hold closed each individual set of contacts of thestepping switches at the proper time or step in the stepping cycle.

One type of commercially available stepping switch which may be utilizedin the mechanism 10 is of the r0 tary type, Model MT-l9 commerciallyavailable from Eagle Signal Corporation of Davenport, Iowa. A solidstate equivalent being Model MT-50 available from the same source. Therotary type of stepping switches utilize a rotary programmable cam foractuating each set of contacts-and which can be readily fixedly attachedand detached from a rotatable camshaft to change the program andsequence of operations. The cycle of each stepping-switch comprises onecomplete 360 revolution of the camshaft. The particular steppingswitches shown have twenty contacts CO-Cl9 and require sixteen steps tocomplete one revolution before the cycle is repeated. Each step rotatesthe camshaft and all the programmed cams fixed thereto onesixteenth of360 or an increment of 22%.The circumferential portion of theconventional interchangeable programcams are likewise divided into thesame number of equal circular segments any one of which can be brokenaway from or left on the cam to engage and close the contacts at thedesired time or step in the cycle.

It can be seen that by providing a sufficient number of limit switches,limit switch actuating cams and the proper contact program such as, aset of programmed cams, in the stepping switches the mechanism 10 can besequenced to position and/or feed most any portion of a casting orworkpiece into engagement with the multi-point cutting tool T. Also, themechanism 10 can be reprogrammed to produce a different number andvariety of movements in most any sequence desired.

OPERATION By way of example, only the programmed sequence of operationof the mechanism 10 for holding, positioning, and feeding variousportions of the particular differential casting C shown into the cuttingtool T will be described.

A source of electrical power is supplied to the various limit switchesLS1-LS13 and other electrical components by closing a main line switchMSW. Selector switches SS1 and SS2 are positioned to supply power fromL1 to the contacts of steeping switches ST2 and ST4. Switch SW1 isclosed to ready cycle. Closing switch SW2 starts the cutting tool drivemotor GM. Closing SW3 starts the fluid pump drive motor FM tosupply'fluid under pressure through the supply lines S. Fluid underpressure passes through conventional adjustable pressure reducing valves196, 198 and a conventional adjustable throttle valve 200 to thepressure ports of the respective directional control valves VX, V2, andVA. Similarly, fluid under pressure is supplied directly from the linesS to the pressure ports of the directional control valves VB, VC, VB andVD through which it passes to the right side of the lock pin clampingcylinder 40 to withdraw the tapered lock pin 46 from engagement with thelever arm 26.

The work clamping cylinder 104, the work clamps 96, the cross feedpiston 160b, and the carriage 16 are retracted to the work loading, orstop and starting position shown in FIGS. 7, 5, 8 and by phantom linesin FIG. 2. Clutch means 62, rotary actuator 30, and rotary fluid motor120 are deactuated maintaining the workholder and the work support headgenerally in the starting positions shown. The normally open contacts ofthe limit switches LS2, LS3, LS6 and LS8 are held closed by theadjustablecams, the normally open contacts of limit switches LS1, LS4,LS5, LS7, LS9, L810, LS11, and LS13 are open and the normally closedcontacts of LS12 are held open by the withdrawn tapered lock pin 46.

There are four identical stepping switch mechanisms STl, ST2, ST3 andST4 each of which has 20 contacts indicated by characters CO and C19placed adjacent one only of each pair of the simultaneously actuatedstepping switches STl, ST2, ST3 and ST4. Each stepping switch hascompleted 16 steps or one revolution for a total of 32 steps and are nowin the loading or stop and start position. Contacts C16 and C19 ofstepping switch STl and contacts C14, C16, C17 and C18 of steppingswitch ST3 are closed. Contacts C13, C16, C17, C18 and C19 of ST2 andcontacts C13 and C19 of ST4 are closed.

The finished casting C is removed and/or another unfinished casting C isplaced onto the workholder 90 with the locating pin 94 in the locatinghole of the casting C. Push button FBI is momentarily closed causingContacts C9 of ST1 and C7 and C9 the stepping switches ST1 and ST2 toadvance to the first position or cycle start position of the mechanismContacts C16 and C19 of ST1 and contacts C13, C16, C17, C18 and C19 ofST2 open.

Contacts C2, C17, C18 of ST1 and contacts C9, C10, C11, C12 and C14 ofST2 close, energizing solenoids SD, SE, and SC which actuate the controlvalves VD, VB and VC. The tapered lock pin 46 is shifted to the rightinto locking engagement with thelever arm 26 allowing normally closedcontacts of L812 to close. Clutch 62 is actuated to prevent relativemotion between the worlcholder 90 and the work support head housing 22and the casting C is' clamped to the workholder by the clamping cylinder104.

Closing push button PB2 completes a circuit through now closed SW1 toadvance stepping switches ST1 and ST2 to the second position. ContactsC9, C16, C18 and C of ST1 and contact C7 of ST2 close energizingsolenoid SX+ shifting spool in valve VX to the left. Fluid underpressure passes through a pipe 202 a check valve 204 into the right endof traversing cylinder 172 and traverses the carriage 16 toward the leftat a rate controlled by a throttle valve 206 in the pipe 208 throughwhich the fluid exhausts from the opposite end of the I cylinder throughvalve VX and return line R to the reservoir 190. Closed limit switch LS8opens and cam 180a actuates LS7 when the right-hand flat window wall ofcasting C is properly aligned'with the left corner and side face ofgrinding wheel shown by example only as the multi-pointed cutting toolT. Closing contacts of open de-energizing solenoid SB+ allowing spool ofvalve VB to center and stopping movement of rotary actuator which holdscasting C in position. The previously held closed contacts of LS6 open.Closing contacts C5 of ST2 energizes solenoid SZ+ shifting spool invalve VZ to left and allowing fluid under pressure, controlled by thepressure reducing valve 198, to pass through pipe 222 and check valve224 into the forward end of the cross feed cylinder 160. Piston 160b,piston rod 160e, the feed screw 158, cross feed bar 152, link bars 142,the carriage 16, work support head 20, and the workholder are pivotedabout the longitudinal axis of shaft 14 towards the cutting tool T. Asthe carriage 16 pivots about axis of the support shaft 14, the initialangular position of the longitudinal axis of both the casting C andworkholder 90 is maintained by the four bar linkage system including thetie rod 38. The right-hand flat side of the casting C is fed into theleft corner of the cutting tool T, and with its longitudinal axissubstantially normal to the axis of rotation of the cutting tool T.Cross feed rate is controlled by a throttle valve 226 in pipe 228through which fluid exhausts from the cylinder 160. Excess cast materialis removed from the right-hand flat side of the housing to the flange ofcasting C and to a predetermined dimension from its central longitudinalaxis. Contacts of LS2 open and the limit switch LS13 is actuated at theend of the cross feed stroke of piston 160b by the adjustable cam LS7advances the stepping switches ST1 and ST2 one more increment to a thirdposition through the now closed contacts C9 of ST1.

of ST2 open deenergizing solenoids SDand SX+. Contacts C12, of ST1 andcontacts C3, of ST2 close energizing solenoid SB+. Spool incontrol valveVD is shifted, by spring, to the right directing fluid under pressure toright side of cylinder 40. Tapered lock pin 46 is withdrawn, openingcontacts of limit switch LS12. Fluid exhaust from left side of cylinder40 through valve VD to return line R to reservoir 190.

Solenoid SB+ shifts spool of valve VB to the right allowing fluid underpressure through a pipe 210 and check valve 212 into the bottom end ofrotary actuator 30 at a pressure controlled by an adjustable reliefvalve 214. Rack piston 34 is moved upwardly which rotates the gear 32,shaft 24, cam support disc 50, lever arm 26, the work support head 20,the workholder 90 and the casting C toward the cutting tool T. Thecasting C is pivoted about the axis of the shaft 24 until thelongitudinal axis of the workholder 90 and casting C is aligned withand'lies substantially in aiplane passing through the axis of rotationof the cutting tool T and the axis of the pivot drive shaft 24. Fluidexhaust from v the opposite top end of the rota'ryactuator 30 through apipe 216, at a rate controlled by a throttle valve 218,

and the valve VBtQ a return line R and reservoir 190.

. and contacts C5 of ST2 are closed. Contacts C3 of ST2 on cam support'bar 168. I v

Contacts of LS13 close and through previously closed contacts of C15 ofST1 advances the stepping switches ST1 and ST2 to the fifth position.Contacts C5 of ST2 open-de-energizing SZ+ and contacts C4 of ST1 andcontacts C6 of ST2 close energizing solenoid SZ,' shifting valve VZ tothe right and passing fluid under pressure through pipe 228 and a checkvalve 230 into the rear side of cylinder 160. Piston 16012 retractscarriage 16 and hence casting C, cam support bar 168 away from cuttingtool where upon limit switch LS2 is closed by cam 170. Stepping switchesST1 and ST2 advance to the sixth position opening contacts C4 of ST1, C6and C10 of ST2 open. Contacts C6 of ST1 and contacts C1 of ST2, close.Opening contacts C10 of ST2 de-energizes solenoid SE shifting valve VEto the right allowing fluid to'exhaust from and deactuate fluid brake orclutch 62. Opening contacts C6 of ST2 deenergizes solenoid SZ, spool ofvalve VZ centers stepping movement of carriage 16. Closing contacts C1of ST2 energizes solenoid SA+ shifting control valve VA to the left,passing fluid through a pipe 232, under a pressure controlled by arelief valve 234 to actuate the rotary fluid motor 120. Fluid exhaustsfrom motor 120 through pipe236, under a pressure controlled by reliefvalve 238, and valve VA to return line R at a rate controlled bythrottle valve 200. Motor shafts 120b and 1200, cam support disc 128,shaft 66, and hence the casting C is turned clockwise through the bevelgears 72 and 74. The opposite left-hand flat side of the castingC is nowpositioned opposite the left side face 'of the cutting tool T. In thisposition limit switch'LS4 lenoid SZ+ is energized shifting valve VZ tothe left passing fluid under pressure through pipe 222 to forward end ofcylinder 160. Carriage 16', cam support bar 168, and hence the casting Cis again cross fed into the left-hand corner of the cutting tool T whichremoves excess cast material from the side around the initial left-handwindow of differential housing of casting C.

Instead of rotating the casting 180 as described above the cycle couldhave been programmed to traverse the casting to the right and feed theleft-hand flat side of the casting into the right-hand corner of thecutting tool T.

Limit switch LS13 is again actuated and through closed contacts C15 ofSTI advances the stepping switches ST1 and ST2 to the eighth position.In this step position contacts C15 of STI and C5 of ST2 opende-energizing solenoid SZ+ and contacts C4 of STI and contacts C6 of ST2close energizing solenoid SZ- shifting valve VZ to the right. Fluidunder pressure passes to rear of cylinder 160 to retract carriage 16 andhence the workpiece away from the cutting tool T, whereupon limit switchLS2 is again actuated to advance STl and ST2 to the ninth position.Contacts C4 of STI and C6 of ST2 open de-energizing 82- and spool invalve VZ center. Contacts C8 of STI and C4 of ST2 close energizing SB-and shifting spool in valve VB to the left, passing fluid under pressurethrough a pipe 216 and check valve 219 to the top end of the rotaryactuator 30. Rack piston 34 rotates gear 32, shaft 24, cam support disc50, lever arm 26, the work support head 20, the workholder 90, and thecasting C away from the cutting tool T. Cam 5.4 actuates limit switchLS6 and through close contacts C8 of STI advances STl and ST2 to thetenth step or position Contacts C8 of STI and C4 of ST2 opende-energizing SB, and spool of valve VB centers. Contacts C14 of ST] andC9 of ST2 close energizing solenoid SD shifting valve VD to the leftpassing fluid under pressure to cylinder 40 to insert tapered lock pin46 into aligning hole oflever arm 26. Normally closed limit L12 isactuated by movement of tapered lock pin 46 closing its contacts whichthrough closed contacts C14 of ST] advance STl and ST2 to the eleventhposition. Contacts C14 of ST] open and contacts C of STI and C8 of ST2close energizing solenoid SX- shifting spool of valve VX to the right.Fluid under pressure passes through pipe 208, and check valve 209 intoleft end of traverse cylinder 172. Piston 172a, cam support bar 178,support shaft 14, carriage 16, work support head 20, workholder 90, andhence the casting C are traversed to the right and returned to theposition shown in FIG. 8 at a rate controlled by a throttle valve 205 inpipe 202. Limit switch LS8 is actuated by cam 180 closing its contactsto advance ST] and ST2 the twelfth position. Contacts C10 of STI, C8 andC10 of ST2 open de-energizing solenoids SX- and SE. Spools of valve VXcenters and spool of valve VE shifts to the right allowing fluid toexhaust from and deactuate fluid clutch 62. Contacts C13 of STI and C1of ST2 close energizing solenoid SA+ shifting the spool of valve VA tothe left. Fluid passes through pipe 232 rotating rotary motor 120, andhence the casting C clockwise 180 about its logi'tudinal axis and thenormal axis of the workholder situated almost in a vertical plane and inthe retracted phantom line position shown in FIG. 2.

Cam 130 moved 180 by a previous clockwise movement is again movedclockwise actuating limit switch LS1 1. Stopping switches STl and ST2advance to the thirteenth stop opening contacts C13 of STI and C1 of ST2de-energizing solenoid SA+, deactuating valve VA, and rotary motor 120.Contacts C3 of STI, C5, and C10 of ST2 close energizing solenoids SE andSZ+. Valve VE shifts to actuate clutch 62 and valve VZ shifts to theleft causing a cross feed movement of the carriage 16 to remove asegment of a gate on the periphery of the ring gear mounting flange ofcasting C by the circular cutting face portions of the cutting tool T.At the end of the cross feed, cam 170 actuates limit switch LS1 closingcontacts thereof to advance ST] and ST2 to the next or fourteenthposition. Contacts C3 of STI and C5 of ST2 open de-energizing SZ+ andspool in valve VZ centers. Contacts C4, STl and C6, ST2 close'energizingsolenoid SZ- shifting valve VZ to the right and retracting carriage andflange of casting C away from cutting tool T. Cam 170b actuates limitswitch LS2 and stops STl and ST2 to the next fifteenth position.Contacts C4 of STI and C6 and C10 of ST2 open de-energizing solenoids52- and SE. Spool of valve VE returns, fluid exhausts deactivatingclutch 62, and spool of valve VZ centers. Contacts C6, STl, C1 of ST2close energizing solenoid SA+ shifting control valves VA to left,passing fluid to rotate rotary motor and hence the casting C a shortdistance clockwise about its longitudinal axis unitl cam actuates LS4advancing stopping switch STl and ST2 to their sixteenth and originalstarting position. Contacts C0, C6 and C18 of STI, and C14, C15 of ST2open breaking circuit to stop coils SC of STI and ST2.

Contacts C16, C19 of STI and C13, C16, C17, C18, C19 of ST2 close toready circuits for transferring further sequence of cycle operationsunder the control of the programmed stopping switches ST3 and ST4.Closing contacts C18 of ST2 through now closed contacts C19 of ST4 andSTl energize the stop coils SC of both ST3 and ST4 to advance them totheir first stop and the seventeenth stop in the cycle. Contacts C14 andC16 of ST3, C13 and C19 of ST4 open.

Contacts C15, C19 and C0 of ST3; and C12 and C14 of ST4 close energizingstop coils to advance ST3 and ST4 into their second step but theeighteenth of the cycle. Contacts C15 and C19 of ST3, contacts C12 andC14 of ST4 open. Limit switch and ST3 circuits are now ready to initiatefurther programmed operations. Contacts C12, C14, of ST3, and C9, C10,C11, C13 and C15 of ST4 are closed. Solenoid SE is energized shiftingvalve VB and actuating or engaging clutch 62. ST3 and ST4 are advancedto their third and nineteenth position by a circuit through now closedcontacts of LS12 and C12 of ST3.

In the nineteenth cycle position contacts C12 and C14 of ST3 andcontacts C13 and C15 of ST4 open. Contacts C1 and C15 of ST3, and C5,C12 and C14 of ST4 close. Solenoid SZ+ is energized, shifting controlvalve VZ and cross feeding the flange of casting C into the cutting faceof the cutting tool T. Another segment of the gate on the flange isremoved whereupon cam actuates limit switch LS1. Contacts LS1 close toadvance the stepping switches ST3 and ST4 to their fourth but thetwentieth cycle position. Contacts C1 of ST3 and C5 of ST4 opende-energizing SZ+ and spool in valve VZ centers. Contacts C2 of ST3 andC6 of ST4 close energizing solenoid SZ shifting valve VZ to retractcasting C away from cutting tool until cam 170b actuates LS2. ContactsLS2 close energizing step coils SC of ST3 and ST4 to advance them totheir fifth and twenty-first position of the cycle.

Contacts C2 of ST3, C6 and C10 of ST4 open deenergizing solenoid SEshifting valve VB and deactuating or disengaging the clutch 62. ContactsC3 of ST3 and C1 of ST4 close energizing solenoid SA+ shifting valve VAto the left to actuate rotary motor 120. Motor 120 rotates casting Cclockwise until cam 130 actuates limit switch LS3 which advancesstopping switches ST3 and ST4 to their sixth but the twenty-second cycleposition. Contacts C3 of ST3 and C1 of ST4 open deenergizing solenoidSA+ and spool in valve VA centers to stop rotary motor 120. Contacts C1of ST3 and C5 and C of ST4 close energizing solenoids SE and SZ+shifting valves VE to actuate clutch 62 and valve VZ to feed the lastsegment of the gate on the flange of casting C into the cutting tool T.Cam 170 actuates LS1 which advances ST3 and ST4 to their seventh andtwenty-third cycle positions. Contacts C1 of ST3, C5, and C10 of ST4open de-energizing solenoid 82+ and SE. Spool in valve VZ centersstopping cross feed and valve VE return to allow exhaust from and todeactuate clutch 62. Contacts C4 of ST3 and C2 of ST4 close energizingsolenoid SA shifting spool of valve VA to the right. Fluid underpressure passes into pipe 236 and rotates rotary motor 120 and hence thecasting C counter clockwise. The casting C is rotated against the wheelto smooth over that portion of the flange from which the large gate waspreviously removed during the three previous feed strokes of thecasting, into the cutting tool T. Casting C and cam support disc 128rotate counter clockwise during which time cam 130 actuates limit switchLS4 advancing ST3 and ST4 to their eighth and twenty-fourth step of thecycle. Contacts C4 of ST3 open, contacts C1 1 of ST3 and vC2 of ST4close holding solenoid SA, energized and valve VA shifted to continuecounterclockwise rotation of motor 120 and casting C. Cam 130 actuateslimit switch LS1]. The entire gate portion of the circumferentialsurface of flange on casting C has been engaged and smoothed by thecutting tool T.

Closing contacts L811 stops ST3 and ST4 to their ninth and twenty-fifthcycle position. Contacts C11 of ST3 and C2 of ST4 open de-energizingsolenoid SA-,

spool in valve VA centers stopping rotary motor 120. Contacts C9 of ST3,C6, and C10 of ST4close energizing solenoids SZ- and SE shifting valveV2 to the right and valve VE to the left. Fluid under pressure passesthrough pipe 228 into rear end of cylinder 160 retracting carriage l6,casting C and cam support bar 168 away from cutting tool T and throughvalve VE to actu-- ate clutch 62. Cam 170 actuatesLS9'during retractionof carriage 16 to stop ST3 and ST4 to their tenth and the twenty-sixthcycle position. Contacts C9 of ST3 open and contacts C2 of ST3, C6, andC10 of ST4 close maintaining solenoid SZ energized and valve VZ shiftedto continue retracting carriage 16 and casting C .away from cutting toolT and maintaining the clutch 62 actuated. Near the end of therearward'mov'ement of carriage 16 and the cam support bar 168 cam 170actuates LS2' advancing ST3 andST4 to their eleventh and thetwenty-seventh cycle position. Contacts C2 of ST3,

shifting the control valve VA to the right. Fluid under pressure passestorotate rotary motor 120 counterclockwise. Cam 130a actuates LS4advancing ST3 and ST4 to their twelfth and the twenty-eighth cycleposition. Contacts C4 of ST3 open, contacts C3 of ST3 close and C2 ofST4 remain closed holding solenoid SA energized and motor 120 rotatingcasting C counterclockwise back to the initial work loading and startingposition whown whereupon cam 130 actuates LS3. Contacts of LS3 closestopping ST3 and ST4 to their thirteenth and the twenty-ninth cycleposition. Contacts C3 of ST3, C2 and C11 of ST4 open deenergizingsolenoids SA and SC. Spool in valve VC shifts allowing fluid to exhaustto unclamp casting C, and spool in valve VA centers stopping rotarymotor 120 and rotation of casting C. Contacts C19 of ST3 and C 10 of ST4close energizing the stop coils of ST3 and ST4 solenoid SE, shiftingvalve VB, and applying clutch 62. Stopping switches ST3 and ST4 advanceto their fourteenth and the thirtieth cycle position. Contacts C19 ofST3 remain closed andautomatically advances ST3 and ST4 through theirfifteenth and sixteenth stops and the thirty-first and thirty-secondcycle positions. Thestoppi'ng switchesST3 and ST4 are now in theirsixteenth and original starting position and the thirtysecond cyclestarting position. In this position contacts C15, C19 and C0 of ST3, andcontacts C9, C10, C12, C14 and C15 of ST4 open preventing furtherenergization of step coils ST3 and ST4. Solenoid SD and SE arede-energized allowing VD and VE to shift to the right. Fluid exhaustsfrom and declutches clutch 62. Fluid pressure passes to cylinder 40withdrawing tapered lock pin 46 which actuates and opens normally closedcontacts of LS12. Contacts C14, C16, C17, C18 of ST3 and contacts C13and C19 of ST4 close to ready circuits and transfer further sequence ofprogrammed operations to the control of stopping switches ST1 and ST2 torepeat the programmed snagging cycle described above Closing contactsC16 of ST3 closes circuit to light a lamp L'indicating the end of thesnagging cycle whereby the finished casting is removed and replaced withan unfinished casting.

Semi-automatic means are provided whereby an operator can alternatelypress push buttons PBS and PB9 causing the mechanism 10 to perform theprogrammed sequence of operation step by step. Shifting selector C6, andC10 of ST4 open de-energizing solenoids SZ of ST3, and C2 of ST4 closeenergizing solenoid SA- switch SSl from the position shown intoengagement with the opposite contact of SS1 in line Lla connects L1 toPBS and to the contacts C14 and C17 of ST2 and to contacts C14 of ST4.Normally open push button PBS is connected in a line Llb extendingbetween line L1a and contacts C15 of both'STZ and ST4. Normally openpush button P89 is connected in a line Llc extending between line Llband the contacts C0-C19 of ST2 and through now closed contacts C19 ofST4. Once the casting C is loaded,,pressi ng PBl advances ST1 and ST2 tothe first stop whereupon contacts C 16 and C19 of ST1;C13, C16, C17,C18, and C19 of ST2 open. Contacts C2, C17, and C18 of ST1; contacts C9,C10, C11, C12 and C14 of ST2 close. Tapered lock pin 46 is inserted,clutch 62 is actuated and the casting C is clamped as before described.Pressing PB2 advances ST1 and ST2 to the second step whereupon contactsC2and C17 of ST1, and contacts C12 and C14 of ST2 open. Contacts C9,C16, C18, and C0 of ST1 and contacts C7, C9, C10, Cl 1, C13, and C15 ofST2 close.

Contacts of both ST! and ST3 are connected in parallel and in serieswith all of the limit switches LS1 through L813 in the manner describedabove for automatic operation by the closing of contacts C of STI. Limitswitches can now advance the stopping switches as be fore to stop aprevious movement. However, subsequent movements cannot occur until oneof the push buttons PB8 or PB9 is closed since the shifting of theselector switch SS1 has opened the line between L1 and the contactsC0-C19 of ST2 and ST4. Now electrical current must pass through one ofalternately closed contacts C14 and C of ST3 and ST4. For examplecontacts C14 of ST2 are open and contacts C15 of ST2 are closed at thistime. Closing PB8 closes a circuit through now closed contacts C15 ofeither ST2 or ST4 and through may other closed contacts'of either of ST2or ST4 to the solenoid connected in series therewith. The push buttonsPB8 and P89 must be held closed to continue and complete that particularmovement or operation whereupon the next limit switch in the sequence isoperated to simultaneously advance the stopping switch mechanisms. Inthe following position contacts C15 of either ST2 or ST4 open andcontacts C14 of either ST2 or ST4 close connecting L1 to line Llb. Thus,holding PB8 is closed any longer has no affect and movements stop untilthe operator closes PB9 closing a circuit through any set of closedcontacts C0-C19 of either ST2 or ST4 to the solenoids. The sameprogrammed sequence of operations is continued by alternately pressingand holding PB8 and P89 closed.

Reset means are provided including a reset selector switch SS2 forsimultaneously resetting the pair of stopping switches STl and ST2, anda switch SW4 interlocked to operate simultaneously with SS2 forsimultaneously resetting the pair of stopping switches ST3 and ST4.Simultaneously closing SW4 and shifting SS2 from the position shown intoengagement with contacts of line Lld connects Ll through closed contactsC0, of either ST] or 8T3 which would be closed, to either the contactsC16 and C17 of ST] or the contacts C14 and C15 of 8T3. Since SS2 hasbeen shifted the circuit between L1 and the contacts of both ST2 and ST4is opened. No further movement can take place and the pair of stoppingswitches controlling the program at this time are returned to theirsixteenth or zero starting position. This is done by the program whichalternately opens and closes contacts C16 and C17 of ST4 and of contactsC12 and C13 of ST2 connected in series, therewith, as shown. Hence oneor the other of the alternately opened and closed circuits will beclosed to stop the coils continuously until the contacts C0 of STI andST3 open. Likewise, a pair of alternately opened and closed contacts C14and C15 of ST3 are connected in series with alternately opened andclosed contacts C12 and C13 of ST4. Therefore shifting SS2 to connectline L1 to Lld and closing SW4 will reset ST3 and ST4 to their sixteenthor zero starting position and the thirty-second snagging cycle positionwhereupon contacts C0 of STS open.

It is obvious that the casting C could have been worked upon in adifferent programmed sequence than described above. For example the gateon the flange could have been removed before removing the flash on theflat sides around the right and left-hand windows of the differentialhousing.

Also, the program could have been sequenced to unclamp and automaticallyunload the finished casting into a bin placed adjacent the mechanism 10.The work support head would be pivoted backwardly, upon retracting thecarriage l6, sufficiently to allow the casting to drop off theworkholder. The snagging cycle described above in actual practice takesapproximately twenty-five seconds to complete and is done automaticallyonce that particular casting C is loaded on the mechanism 10 and pushbuttons P81 and PB2 are depressed by the operator. Thus operator fatigueis eliminated and all castings are ground alike, faster, and at a higherfeed rate and pressure than possible by hand. Four basic motions,representing the hand movements required by an operator to grind aboutpercent of the high volume automotive castings can be duplicated by theprogrammed mechanism 10. A set of programmed cams for each of thestopping switch mechanisms, cam support discs, and cam support bars withthe properly spaced predetermined number of cams thereon or equivalentelectrical means, such as printed wiring boards for use with theequivalent solid state stopping switch mechanisms can be made up inadvance for each casting to be worked. The set up or change over processbetween castings taking but a few minutes to accomplish.

The foregoing description of the mechanism shown in the drawings isconsidered as illustrative only of the principles of the invention. Manymodifications and changes may be made of the invention by those skilledin the art without departing from the spirit of this invention.Therefore, it is to be understood that the invention is not limited tothe construction and operation shown as described but includes allmodifications and equivalents falling within the scope of the appendedclaims.

What is claimed is:

l. A mechanism for holding a workpiece, seequentially positioning, andfeeding unwanted portions of the workpiece into engagement with and forremoval by a driven multi-point cutting tool, moving around an axis ofrotation of means for supporting the cutting tool, of a machine tool,comprising:

a support frame fixed relative to the machine tool,

adjacent the multi-point cutting tool;

a carriage slidably and pivotally attached to and extending upwardlyfrom the support frame to a position opposite the cuttingtool, thecarriage being movable along and pivotable relative to the support frameabout a longitudinal axis extending substantially horizontal adjacentthe machine tool;

means for traversing the carriage in opposite directions, along thelongitudinal axis, relative to the support frame and the cutting tool;cross feed means for pivoting the carriage, relative to the supportframe, about the longitudinal axis toward and away from the cuttingtool;

a work support head rotatably mounted on the carriage opposite thecutting tool for pivotal movement, relative to the carriage and thecutting tool, about a pivot axis of the work support head substantiallyparallel to and movable about the longitudinal axis;

means, mounted on and pivotable with the work support head, for holdingand rotating a workpiece about a normal axis substantially perpendicularto the pivot axis relative to the work support head and the cuttingtool;

means, for simultaneously pivoting the work support head and theworkpiece holding and rotating means together about the pivot axisrelative to the carriage and the cutting tool; and

programmed control means operable for actuating and deactuating in apredetermined sequence the means for traversing and pivoting thecarriage along and about the longitudinal axis, the means forsimultaneously pivoting the work support head and the workpiece holdingmeans about the pivot axis, and the means for rotating the workpieceholding means about the normal axis.

2. A mechanism according to claim 1 further com prising; means adjacentto and movable with the carriage, operable for allowing and preventingpivotal movement of the work support head relative to the carriage aboutthe pivot axis and maintaining the workpiece holding meansin' apredetermined angular position relative to the cutting tool; and whereinthe programmed control means further comprises:

means operable for actuating and deactuating in the predeterminedsequence the means operable for allowing and preventing pivotal movementof the support head about the pivot axis.

3. A mechanism according to claim 2 further comprising:

a support shaft attached to the carriage and slidably mounted'in thesupport frame for axial movement along the longitudinal axis.

4;'A mechanism according to claim 3 carriage comprises:

an upwardly extending lever arm connected to the support shaft andhaving a lower portion with a bearing hole through which the supportshaftextends, and to which the support shaft is fixed against axialmovement relative to 'the lever arms, 1 an upper portion with a bearinghole in which the work support head is pivotally mounted.

5. A mechanism according to claim 4 further comprisingr i y i a link barwith a rear end portion pivotally connected to the leverarm to pivotabout an axis substantially parallel torthe longitudinal axis andextending outwardly away from the lever arm and the cutting tool to anopposite forward end portion thereof; across feed bar connected to thecross feed means and pivotally connected to the forward end portion ofthe linkbar to extend lengthwise and pivot about an axis substantiallyparallel to the longitudinal axis and having an elongated slot extendingthrough opposite sides wherein the of the cross feed bar and elongatedlengthwise of the cross feed bar; a tie rod having.

an upper end portion with a ball joint connected to the forward endportion of the link bar a fixed center distance from the pivotalconnection between the rear end portion of the link bar and the leverarm, j g an opposite endportion with a lower ball joint connected to thebase frame a center distance from the longitudinal axis substantiallyequal to the fixed center distance between the pivotal connection andthe upper ball joint, and

the ball joints being spaced a center distance less than a centerdistance between the pivotal connection and the longitudinal axis;

whereby the lever arm, the support frame, the link bar, and the tie rodare pivotally connected to one another and form a four bar linkagesystem constantly changing the angular relationship between the link barand a horizontal plane passing through the longitudinal axis of thesupport shaft and allowing the cross feed means to move the carriagetogether with the workpicce at a relatively constant force during thepivotal movement of the carriage about the longitudinal axis toward thecutting tool.

6. A mechanism according to claim 5 wherein the means for traversing thecarriage in opposite directions along the longitudinal axis comprises:

, a fluid operated traversing cylinder fixed to the support frame,

a traversing piston slidably mounted in the traversing cylinder;

a traversing piston rod connected to the traversing piston and to thesupport shaft.

7. A mechanism according to claim 6 wherein the cross feed means forpivoting the carriage about the longitudinal axis comprises:

a pivot support, fixed relative to the machine tool and the supportframe, adjacent the cutting tool,

a fluid operated cross feed cylinder having one of its end portionspivotally attached to the pivot support for movement in a vertical planeabout a substantially horizontal axis substantially parallel to thelongitudinal axis and normal to a central axis of the cross feedcylinder,

a cross feed piston slidably mounted in the cross feed cylinder,

a cross feed piston rod connected to and extending from the cross feedpiston through the opposite end of the cylinder,

a threaded rod coupled to the cross feed piston rod and extendingthrough the elongated slot in the cross feed bar,

a hand wheel, threaded onto the threaded rod, and having a portionextending into the elongated slot, and fixed against axial movementrelative to the cross feed bar, 7

whereby the elongated slot allows the cross feed bar totraverse relativeto the handwheel and the cross feedmeans during 'a traversing movementof the carriage along the longitudinal axis and rotation of thehandwheel shifts the handwheel and the cross feed bar axially relativeto the threaded rod, and the position of the carriage and the pivot axisof the work support head relative to the cutting tool.

8. A mechanism according to claim 7 wherein the work support headcomprises:

a work support housing rotatably supported opposite the cutting toolby'the lever arm and fixed against axial movement relative to the upperportion of the lever arm;

a pivotal drive shaft fixed to and extending from a side of the housingthrough the bearing hole in the upper portion of the lever arm;

a hollow driven shaft fixed to and extending from an opposite side ofthe work support housing and driven in axial alignment with the pivotaldrive shaft and the pivot axis.

9. A mechanism according to claim 8 wherein the means for holding androtating a workpiece about the normal axis relative to the work supporthead comprises:

a workholder drive shaft rotatably mounted in the work support housingfor rotation about the normal axis, having an upper end portionextending through and beyond a side wall of the work support housing andfixed against axial movement relative to the work support housing;

a workholder drive gear fixed to and rotatable with the workholder driveshaft within the housing;

a workholder support base fixed to the upper end position for rotationwith the workholder drive shaft; and

means, adapted to mate with; be fixed to, and removable from theworkholder support base for locating and clamping the workpiece in apredetermined position;

a driving gear drive shaft rotatably mounted within the hollow drivenshaft and having an end portion extending into the housing;

a driving gear fixed to the end portion of the driving gear drive shaftextending into the housing and in driving engagement with the workholderdrive gear; and

a reversible fluid operated rotary motor attached to, rotatable with,and supported by an opposite end portion of the hollow driven shaft andhaving an output drive shaft coupled to rotate the driving gear driveshaft relative to the hollow driven shaft, and

clutch means, coupled to the driving gear drive shaft, the output driveshaft and to the hollow driven shaft, operable for allowing andpreventing relative rotary motion between the driving gear drive shaftand the hollow driven shaft and between the workpiece holding means andthe work support head. 10. A mechanism according to claim 9 wherein themeans operable for allowing and preventing pivotal movement of the worksupport head relative to the carriage and maintaining the normal axis ofthe workpiece holding means in the predetermined angular positioncomprises:

a workpositioning arm fixed to the pivotal drive shaft -to extend,normal to the pivot axis, adjacent the lever arm of the carriage andhaving a locating hole with an axis located a predetermined distancefrom the pivot axis;

a torque arm adjacent the work positioning arm hava hole through whichthe pivotal drive shaft extends into and through the means for pivotingthe work support head fixed to the torque arm, the torque arm beingpivotable relative to and with the pivotal drive shaft about thelongitudinal axis and having a short lever arm portion extending normalto and from the pivot axis,

a hole in the short lever arm portion axially alligned with the locatinghole in the work positioning arm,

a long lever arm portion extending normal to the pivot axis opposite theshort lever arm portion;

a second tie rod having an upper end portion with an upper ball jointconnected to the long arm portion a fixed center distance from the pivotaxis, a lower end portion with a lower ball joint connected to thesupport frame a center distance from the longitudinal axis substantiallyequal to the fixed center distance, the ball joints being spaced acenter distance substantially equal to a center distance between thelongitudinal axis and the pivot axis; and means for aligning the holes,engaging, and locking the work positioning arm to the short lever armportion of the torque arm; whereby the long lever arm portion of thetorque arm, the lever arm, the second tie rod, and the support frame arepivotally connected together at the pivot axis, the longitudinal axis,and axes of the ball joints and provide a four bar parallel linkagesystem maintaining the position of torque arm the work support head andthe normal axis of the workpiece holding means relative to the cuttingtool during a pivotal movement of the carriage about the longitudinalaxis.

11. A mechanism according to claim 10 wherein the means forsimultaneously pivoting the work support .head and the workpiece holdingand rotating means together about the pivot axis comprises:

a reversible fluid operated rotary actuator comprising:

a body fixed to the torque arm and mounted on a portion of the pivotaldrive shaft rotatable within and extending through spaced bearing holesin the body;

a gear fixed and rotatable with the pivotal drive shaft;

a rack piston slidably mounted within a cylinder bore in the body andhaving rack teeth in driving engagement with the gear;

whereby movement of the rack piston in opposite directions rotates thegear, the pivotal drive shaft and the work support head in oppositedirections relative to the carriage and the cutting tool.

12. A mechanism according to claim 11 wherein the programmed controlmeans comprises:

a plurality of removable cam supports fixed for movement with thepivotal drive shaft, the driving gear drive shaft, the cross feed pistonrod, and the traversing piston rod;

a plurality of cams fixed in predetermined positions on the camsupports;

a plurality of limit switches fixed adjacent the cam supports foractuation by the cams;

at least one programmed step switch mechanism having 1 a plurality ofsets of contacts programmed to open and close in a predeterminedsequence,

a set of the plurality of sets of contacts connected in series with eachof the limit switches to a source of power and to means for actuatingeach stepping switch mechanism;

whereby the actuation of a limit switch to close its contacts, and theprogrammed closed contacts of the step switch mechanism in seriestherewith closes a circuit to simultaneously actuate and advance thestep switch mechanism one step of a programmed cycle of operation.

1. A mechanism for holding a workpiece, seequentially positioning, andfeeding unwanted portions of the workpiece into engagement with and forremoval by a driven multi-point cutting tool, moving around an axis ofrotation of means for supporting the cutting tool, of a machine tool,comprising: a support frame fixed relative to the machine tool, adjacentthe multi-point cutting tool; a carriage slidably and pivotally attachedto and extending upwardly from the support frame to a position oppositethe cutting tool, the carriage being movable along and pivotablerelative to the support frame about a longitudinal axis extendingsubstantially horizontal adjacent the machine tool; means for traversingthe carriage in opposite directions, along the longitudinal axis,relative to the support frame and the cutting tool; cross feed means forpivoting the carriage, relative to the support frame, about thelongitudinal axis toward and away from the cutting tool; a work supporthead rotatably mounted on the carriage opposite the cutting tool forpivotal movement, relative to the carriage and the cutting tool, about apivot axis of the work support head substantially parallel to andmovable about the longitudinal axis; means, mounted on and pivotablewith the work support head, for holding and rotating a workpiece about anormal axis substantially perpendicular to the pivot axis relative tothe work support head and the cutting tool; means, for simultaneouslypivoting the work support head and the workpiece holding and rotatingmeans together about the pivot axis relative to the carriage and thecutting tool; and programmed control means operable for actuating anddeactuating in a predetermined sequence the means for traversing andpivoting the carriage along and about the longitudinal axis, the meansfor simultaneously pivoting the work support head and the workpieceholding means about the pivot axis, and the means for rotating theworkpiece holding means about the normal axis.
 2. A mechanism accordingto claim 1 further comprising: means adjacent to and movable with thecarriage, operable for allowing and preventing pivotal movement of thework support head relative to the carriage about the pivot axis andmaintaining the workpiece holding means in a predetermined angularposition relative to the cutting tool; and wherein the programmedcontrol means further comprises: means operable for actuating anddeactuating in the predetermined sequence the means operable forallowing and preventing pivotal movement of the support head about thepivot axis.
 3. A mechanism according to claim 2 further comprising: asupport shaft attached to the carriage and slidably mounted in thesupport frame for axial movement along the longitudinal axis.
 4. Amechanism according to claim 3 wherein the carriage comprises: anupwardly extending lever arm connected to the support shaft and having alower portion with a bearing hole through which the support shaftextends, and to which the support shaft is fixed against axial movementrelative to the lever arms, an upper portion with a bearing hole inwhich the work support head is pivotally mounted.
 5. A mechanismaccording to claim 4 further comprising: a link bar with a rear endportion pivotally connected to the lever arm to pivot about an axissubstantially parallel to the longitudinal axis and extending outwardlyaway from the lever arm and the cutting tool to an opposite forward endportion thereof; a cross feed bar connected to the cross feed means andpivotally connected to the forward end portion of the link bar to extendlengthwise and pivot about an axis substantially parallel to thelongitudinal axis and having an elongated slot extending throughopposite sides of the cross feed bar and elongated lengthwise of thecross feed bar; a tie rod having an upper end portion with a ball jointconnected to the forward end portion of the link bar a fixed centerdistance from the pivotal connection between the rear end portion of thelink bar and the lever arm, an opposite end portion with a lower balljoint connected to the base frame a center distance from thelongitudinal axis substantially equal to the fixed center distancebetween the pivotal connection and the upper ball joint, and the balljoints being spaced a center distance less than a center distancebetween the pivotal connection and the longitudinal axis; whereby thelever arm, the support frame, the link bar, and the tie rod arepivotally connected to one another and form a four bar linkage systemconstantly changing the angular relationship between the link bar and ahorizontal plane passing through the longitudinal axis of the supportshaft and allowing the cross feed means to move the carriage togetherwith the workpicce at a relatively constant force during the pivotalmovement of the carriage about the longitudinal axis toward the cuttingtool.
 6. A mechanism according to claim 5 wherein the means fortraversing the carriage in opposite directions along the longitudinalaxis comprises: a fluid operated traversing cylinder fixed to thesupport frame, a traversing piston slidably mounted in the traversingcylinder; a traversing piston rod connected to the traversing piston andto the support shaft.
 7. A mechanism according to claim 6 wherein thecross feed means for pivoting the carriage about the longitudinal axiscomprises: a pivot support, fixed relative to the machine tool and thesupport frame, adjacent the cutting tool, a fluid operated cross feedcylinder having one of its end portions pivotally attached to the pivotsupport for movement in a vertical plane about a substantiallyhorizontal axis substantially parallel to the longitudinal axis andnormal to a central axis of the cross fEed cylinder, a cross feed pistonslidably mounted in the cross feed cylinder, a cross feed piston rodconnected to and extending from the cross feed piston through theopposite end of the cylinder, a threaded rod coupled to the cross feedpiston rod and extending through the elongated slot in the cross feedbar, a hand wheel, threaded onto the threaded rod, and having a portionextending into the elongated slot, and fixed against axial movementrelative to the cross feed bar, whereby the elongated slot allows thecross feed bar to traverse relative to the handwheel and the cross feedmeans during a traversing movement of the carriage along thelongitudinal axis and rotation of the handwheel shifts the handwheel andthe cross feed bar axially relative to the threaded rod, and theposition of the carriage and the pivot axis of the work support headrelative to the cutting tool.
 8. A mechanism according to claim 7wherein the work support head comprises: a work support housingrotatably supported opposite the cutting tool by the lever arm and fixedagainst axial movement relative to the upper portion of the lever arm; apivotal drive shaft fixed to and extending from a side of the housingthrough the bearing hole in the upper portion of the lever arm; a hollowdriven shaft fixed to and extending from an opposite side of the worksupport housing and driven in axial alignment with the pivotal driveshaft and the pivot axis.
 9. A mechanism according to claim 8 whereinthe means for holding and rotating a workpiece about the normal axisrelative to the work support head comprises: a workholder drive shaftrotatably mounted in the work support housing for rotation about thenormal axis, having an upper end portion extending through and beyond aside wall of the work support housing and fixed against axial movementrelative to the work support housing; a workholder drive gear fixed toand rotatable with the workholder drive shaft within the housing; aworkholder support base fixed to the upper end position for rotationwith the workholder drive shaft; and means, adapted to mate with, befixed to, and removable from the workholder support base for locatingand clamping the workpiece in a predetermined position; a driving geardrive shaft rotatably mounted within the hollow driven shaft and havingan end portion extending into the housing; a driving gear fixed to theend portion of the driving gear drive shaft extending into the housingand in driving engagement with the workholder drive gear; and areversible fluid operated rotary motor attached to, rotatable with, andsupported by an opposite end portion of the hollow driven shaft andhaving an output drive shaft coupled to rotate the driving gear driveshaft relative to the hollow driven shaft, and clutch means, coupled tothe driving gear drive shaft, the output drive shaft and to the hollowdriven shaft, operable for allowing and preventing relative rotarymotion between the driving gear drive shaft and the hollow driven shaftand between the workpiece holding means and the work support head.
 10. Amechanism according to claim 9 wherein the means operable for allowingand preventing pivotal movement of the work support head relative to thecarriage and maintaining the normal axis of the workpiece holding meansin the predetermined angular position comprises: a work positioning armfixed to the pivotal drive shaft to extend, normal to the pivot axis,adjacent the lever arm of the carriage and having a locating hole withan axis located a predetermined distance from the pivot axis; a torquearm adjacent the work positioning arm having a hole through which thepivotal drive shaft extends into and through the means for pivoting thework support head fixed to the torque arm, the torque arm beingpivotable relative to and with the pivotal drive shaft about thelongitudinal axis and having a short lever arm portion extending normalto and from the pivot axis, a hole in the short lever arm portionaxially alligned with the locating hole in the work positioning arm, along lever arm portion extending normal to the pivot axis opposite theshort lever arm portion; a second tie rod having an upper end portionwith an upper ball joint connected to the long arm portion a fixedcenter distance from the pivot axis, a lower end portion with a lowerball joint connected to the support frame a center distance from thelongitudinal axis substantially equal to the fixed center distance, theball joints being spaced a center distance substantially equal to acenter distance between the longitudinal axis and the pivot axis; andmeans for aligning the holes, engaging, and locking the work positioningarm to the short lever arm portion of the torque arm; whereby the longlever arm portion of the torque arm, the lever arm, the second tie rod,and the support frame are pivotally connected together at the pivotaxis, the longitudinal axis, and axes of the ball joints and provide afour bar parallel linkage system maintaining the position of torque armthe work support head and the normal axis of the workpiece holding meansrelative to the cutting tool during a pivotal movement of the carriageabout the longitudinal axis.
 11. A mechanism according to claim 10wherein the means for simultaneously pivoting the work support head andthe workpiece holding and rotating means together about the pivot axiscomprises: a reversible fluid operated rotary actuator comprising: abody fixed to the torque arm and mounted on a portion of the pivotaldrive shaft rotatable within and extending through spaced bearing holesin the body; a gear fixed and rotatable with the pivotal drive shaft; arack piston slidably mounted within a cylinder bore in the body andhaving rack teeth in driving engagement with the gear; whereby movementof the rack piston in opposite directions rotates the gear, the pivotaldrive shaft and the work support head in opposite directions relative tothe carriage and the cutting tool.
 12. A mechanism according to claim 11wherein the programmed control means comprises: a plurality of removablecam supports fixed for movement with the pivotal drive shaft, thedriving gear drive shaft, the cross feed piston rod, and the traversingpiston rod; a plurality of cams fixed in predetermined positions on thecam supports; a plurality of limit switches fixed adjacent the camsupports for actuation by the cams; at least one programmed step switchmechanism having a plurality of sets of contacts programmed to open andclose in a predetermined sequence, a set of the plurality of sets ofcontacts connected in series with each of the limit switches to a sourceof power and to means for actuating each stepping switch mechanism;whereby the actuation of a limit switch to close its contacts, and theprogrammed closed contacts of the step switch mechanism in seriestherewith closes a circuit to simultaneously actuate and advance thestep switch mechanism one step of a programmed cycle of operation.
 13. Amechanism according to claim 12 wherein the means for locating andclamping the workpiece comprises: a work locating arbor fixed to thework support base and having a central hole extending axiallytherethrough, a slot extending transversely to the axis of the hole andthrough an upper end portion of the locating arbor, and upper and lowercamming surfaces on upper and lower portions, of the slots, on oppositesides of the central hole; means for orienting the workpiece on thelocating arbor; a clamp actuating rod slidably mounted in the centralhole of the locating arbor and extending through the workholder driveshaft to an opposite side of the work support housing; a pair of clampsadapted to engage the camming surfaces and the workpiece, pivotallyconnected to the clamp actuating rod and eXtending in oppositedirections in the slot; and a fluid operated clamping cylinder mountedon the work support housing and having a piston slidably mounted in theclamping cylinder, a piston rod connected to the piston and to theclamping rod; whereby shifting the clamp actuating rod axially in onedirection causes the lower camming surfaces to retract the clamps withinthe slot and shifting the clamping rod in an opposite direction causesthe clamps to engage the upper camming surfaces forcing the clampsoutwardly into clamping engagement with the workpiece.
 14. A mechanismaccording to claim 13 wherein the means for aligning the holes engaging,and locking the work positioning arm to the short lever arm portioncomprises: a fluid operated lock pin cylinder fixed to the body of therotary actuator adjacent the aligned holes in the short arm portion ofthe torque arm; a lock pin piston slidably mounted in the lock pincylinder, a lock pin piston rod attached to the lock pin piston, atapered lock pin fixed to an opposite end of the lock pin piston rod inaxial alignment with the holes in the short arm portion and the workpositioning arm; whereby movement of the lock pin piston in oppositedirections causes a corresponding movement of the lock pin into and outof the aligned holes and locking engagement with the short lever armportion and the work positioning arm.
 15. A mechanism according to claim14 wherein the programmed control means further comprises: a pluralityof solenoid operated directional control valves connected to thetraversing cylinder, the cross feed cylinder, the rotary actuator, therotary motor, the lock pin cylinder, the clamping cylinder, and theclutch means, each solenoid connected in series with a set of programmedcontacts of the programmed stepping switch mechanism to the source ofpower, whereby closing of the contacts in the predetermined sequenceactuates the solenoids and the fluid flow control valves directing fluidunder pressure to actuate the traversing cylinder, the cross feedclyinder, the rotary actuator, the rotary motor, the lock pin clyinder,the clamping cylinder, and the clutch means in the predeterminedsequence.
 16. A mechanism according to claim 15 wherein the programmedcontrol means further comprises: at least a second programmed steppingswitch mechanism having a set of programmed contacts connected in serieswith each of the limit switches and in parallel with each set of theprogrammed contacts of the first mentioned stepping switch mechanismconnected in series with each of the limit switches; and a set ofprogrammed contacts connected in series with each of the solenoids andin parallel with each set of the programmed contacts of the firstmentioned stepping switch mechanism connected in series with each of thesolenoids; whereby a larger number of programmed contacts and steps areprovided than might be available in the first stepping switch mechanismto produce an additional number of movements necessary to finish theworkpiece.
 17. A mechanism according to claim 16 wherein the programmedcontrol means further comprises: means, including a pair of normallyopen manually operated switches each of which is connected in serieswith a set of a pair of alternately opened and closed programmedcontacts of the step switch mechanism and to the programmed contactsconnected in series with the solenoids, for manually actuating thesolenoids one at a time in the predetermined programmed sequence,deactuating the solenoids, and manually controlling programmed movementsof the mechanism; whereby the normally open switches must be alternatelyoperated and held closed to maintain one of the solenoids energized tocomplete one of the programmed movements, and until one of the camsactuates one of the limit switches, the step switch mechanism one stepopening the closed set of the pair of alternately opened and closedprogrammed contActs deenergizing the one solenoid and stepping the onemovement and closing the opened set of the pair of alternately openedand closed programmed contacts in series with the other one of the pairof normally open switches, and the other one of the pair of normallyopen switches must be actuated and held closed to start and completeanother one of the movements of the programmed movements.
 18. Amechanism according to claim 17 wherein the programmed control meansfurther comprises: a third stepping switch mechanism connected inparallel stepping and actuated simultaneously with the first mentionedstopping switch and having a plurality of programmed contacts programmedto open and close in the predetermined sequence, and a set of theprogrammed contacts connected in series with each of the solenoidsconnected in series to the source of power; whereby the first and thirdstepping switch mechanisms are actuated simultaneously, the solenoidsare separated from the first stepping switch and connected to and solelyunder the control of the individually programmed third stepping switchmechanism.
 19. A mechanism according to claim 18 wherein the programmedcontrol means further comprises: a fourth stepping switch mechanismconnected in parallel with and actuated simultaneously with the secondmentioned stepping switch mechanism and having a set of programmedcontacts connected in series with each of the solenoids and in parallelwith each set of the programmed contacts of the third mentioned steppingswitch mentioned connected in series with the solenoids; whereby anadditional number of programmable contacts and steps are available inthe first and second stepping switches for connection to the limitswitches, an additional number of programmed contacts and steps areavailable in the second and fourth stepping switches for connection tothe solenoids, and the solenoids are separated from the first and secondstepping switches mechanisms and connected solely to and under thecontrol of the third and fourth stepping switches.
 20. A mechanismaccording to claim 19 further comprising: a second upwardly extendinglever arm on the carriage spaced from and connected to the firstmentioned lever arm and to the support shaft and having a lower portionwith a bearing hole through which the support shaft extends and to whichthe support shaft is fixed against axial movement relative to the leverarm, an upper portion with a bearing hole in which the hollow drivenshaft of the work support head is pivotally mounted with the worksupport housing situated between the upper portions of the lever arms;and a second link bar with a rear end portion pivotally connected to thesecond lever arm for relative movement about an axis aligned with theaxis of pivotal connection between the first mentioned link bar andlever arm and extending outwardly away from the second lever arm and thecutting tool substantially parallel to the first mentioned link bar to asecond opposite forward end portion connected to the upper ball joint ofthe tie rod and the first mentioned forward end portion, the secondforward end portion being pivotally connected to an opposite end of thecross feed bar for movement about an axis aligned with the axis of thepivotal connection between the first mentioned link bar and the crossfeed bar.
 21. A mechanism for holding a workpiece, sequentiallypositioning, and feeding unwanted portion of the workpiece intoengagement with and for removal by a driven multi-point cutting tool,moving around an axis of rotation of means for supporting the cuttingtool, of a machine tool, comprising: a support frame fixed relative tothe machine tool, adjacent the multi-point cutting tool; carriage meansslidably attached to and extending upwardly from the support frame to aposition opposite the cutting tool, the carriage means being movablerelative to the support frame along a longitudinal axis extendingsubstantially horizontal adjacent the machine tool and toward and awayfrom the cutting tool; means for traversing the carriage means inopposite directions, along the longitudinal axis, relative to thesupport frame and the cutting tool; cross feed means for moving thecarriage means, relative to the support frame, toward and away from thecutting tool; a work support head rotatably mounted on the carriagemeans opposite the cutting tool for pivotal movement, relative to thecarriage means and the cutting tool, about a pivot axis of the worksupport head including a work support housing and a hollow shaft fixedto and extending from a side of the work support housing, rotatablysupported by the carriage means and driven about the pivot axis; means,mounted on and pivotable with the work support head about the pivotaxis, for holding and rotating a workpiece about a normal axissubstantially perpendicular to the pivot axis relative to the worksupport head and the cutting tool including a workholder drive shaftrotatably mounted in the work support housing for rotation about thenormal axis a workholder, fixed to the workholder drive shaft, forlocating and clamping the workpiece in a predetermined position a shaftmounted within the hollow shaft for rotation about the pivot axis, andreversible drive means, connected to and for simultaneously rotating theshaft within the hollow shaft about the pivot axis relative to thehollow shaft and the workholder drive shaft about the normal axis;means, for simultaneously pivoting the work support head and theworkpiece holding and rotating means together about the pivot axisrelative to the carriage means and the cutting tool; and programmedcontrol means operable for actuating and deactuating in a predeterminedsequence the means for traversing the carriage means along thelongitudinal axis, the cross feed means for moving the carriage meanstoward and away from the cutting tool, the means for simultaneouslypivoting the work support head and the workpiece holding means about thepivot axis, and the means for rotating the workpiece holding means aboutthe normal axis.
 22. A mechanism according to claim 21 furthercomprising: means adjacent to and movable with the carriage means,operable for allowing and preventing pivotal movement of the worksupport head relative to the carriage means about the pivot axis andmaintaining the workpiece holding means in a predetermined angularposition relative to the cutting tool; and wherein the programmedcontrol means further comprises: means operable for actuating anddeactuating in the predetermined sequence the means operable forallowing and preventing pivotal movement of the support head about thepivot axis.